The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 21, 2000
Filed:
May. 12, 1999
Keiji Iimura, Itabashi-ku, Tokyo 175-0092, JP;
Other;
Abstract
A flat light source with U-shaped configuration is proposed which can provide substantially uniform surface illumination. The flat light source includes a first transparent portion for use for illumination which may be composed of a first substantially flat light transmission means, a second transparent portion for use as bypass light guide which may be composed of a second substantially flat light transmission means, and a light coupling portion for use as light coupling between said first and second transparent portions, which may have at least one optical prism. The first and second transparent portions which may be positioned substantially parallel each other form a first and second substantially linear cross sections of a substantially U-shaped configuration. The light coupling portion which is positioned near a bottom between said first and second transparent portions forms a substantially bent (or non-linear) cross section of the U-shaped configuration. Thereby the flat light source composed of the first transparent portion, the second transparent portion and the light coupling portion forms the U-shaped configuration as a whole.